The present invention generally relates to an electronic security system and, more particularly, to a system which has at least one electronic user key having combination codes on two ends of the user key thereby allowing the user key access to at least two different locks.
Presently, there are many electronic lock systems which employ an encoded key card. Typically the key card has a code combination encoded on one end. If the code combination on the key matches the code combination in the lock a certain function is performed by the lock, such as opening the lock mechanism. The key card can also be encoded with a second code combination on the same end so that the code combination in the lock can be updated by replacing the lock code combination with the second key code combination. Such a security system is described in U.S. Pat. No. 4,283,710 to Genest.
The invention disclosed by Genest in U.S. Pat. No. 4,283,710 describes a security system with a lock having multi-level memories with each level identified by an identification code. Thus, a number of locks may have the same code combination at a certain memory level, thereby allowing a single type of key to open a plurality of locks. A particular application for this may be for a maid to service a certain floor or the hotel manager to have a "master" key to open every lock in the hotel. However, the guest key will only open one room. For example, at level 1 of the memory, each lock would have a different code combination. At level 2 memory, the code combinations for an entire floor would be the same thus allowing the maid to service each of the rooms on the individual floor. All the code combinations of level 3 memory would be the same, thus allowing the manager to open all the locks in the hotel.
Therefore, the locks described above have multiple memories to allow different keys to open the same door. However, the security system described does not allow two different locks, each with different code combinations, to be opened by the same key. For example, it may be desired to allow a guest to have access to the hotel room and a fire exit or any other common area. Such a common area could be locked, and therefore require a certain lock code combination to open it. All the lock code combinations for every room on the floor could be placed within the memory of the lock for the common area. However, this would be very impractical.
Therefore, there is a current need for a security system which would allow a single user key to access more than one door where each door lock has a different lock code combination.